According to Haynes Manual
0304 = Knock sensor or circuit fault
0807 = Avap canister purge control valve circuit fault
0504 = A/T control unit or circuit fault
( Auto Transmision ? )

the only symptoms i feel on my car is when it shifts to 3rd at about 3.2 krpm i lose power for a couple of seconds. I've been feeling this symptom for months though, since my battery went dead one day ( left lights on )

only other info:
-i had to drive around without fog lights due to fender bender. ( water damage anywhere in there ? )
-NY weather been acting up...
-my left head light ( low beam ) blew out 3 times in a row in the course of two days.

( i know all these may be unrelated.. but i am just listing all my "car troubles" to see if anyone can relate )

HELP!!!!!!

 

Regards to your Mil.light

A knock sensor will not turn on the light,ever.
Sounds like a o2 sensor problem.Yes an evap valve and the purge control valves and or the wiring are very common.
The wiring at the evap valve and the purge valve use the same power source,so with the ignition key on,check the both plugs for power,check the evap plug first.If the their
is no power,undue the tape rapping to wear the two wires tie off.You will find corotted wires.

Good Luck!!

 

More info that may help

Regarding Mil light,If the engine (cranks,turns over)
but takes a long time to start cold or warm,known
problem,crank angle sensor harness open.Wires rub through
against the power steering pump.The complete harness
(sub.harness)would have to be replaced.Big job,dealer
type job.(Their is a TSB about it)So have your self- diognosis done.

Again Good luck!!!

 

i am going to try to make sense of all this.. thanks for the reply !

 

So... nissan says

Need new knock sensor, new boost sensor and .

your water separator kit is missing, you need a new one

HUH?!

-i know where the knock sensor is. that requires i take off the intake manifold (nissan says one hour at least for that)

-he told me it's common to lose the water separator kit, or.. that in the 96 model.. there was a modification needed on this or recomended on this that my dealer could have done

-as for the boost sensor ?? no clue.

I'll look in haynes manual for these things... they seem simple enough .. but might it be worth labor cost / pain to get it done for me ?

 

Reguards to the knock sensor,the code can be clear by removing the sensor and cleaning the the sensor and it's rusted surface but the code will come back after a few months.This sensor will not turn on the light,but will be in memory So don't worry about it.to buy another sensor is a waste of money seeing that it's only a ground fault between the sensor and the block.As for the boost sensor,it's located on the air intake that is mounted on the rad support,has a elec.plug and a vacum hose.(same idea as a map sensor)It will give a hard code but suggest to make sure the vacum hoses are not mixed up and holes.As for the water seperator,this is part of the evap system and their is a TSB reguarding the seperator.The up date was to add the seperator and hose and small filter that goes on the out let of the water sep.This filter or screen WILL
plug up and also turn on the mil. light

Hope this info helps
ENJOY THE RIDE!!!

 

n/m

 

Regards to TSB,Technical service bulletin,check with your Nissan dealer.
RAD,radiator????Give me more info wanted!!!!
Regards to your shifting and or slight hesitation
since battery died,go to the dealer and have self-learn
cleared.This could be at fault.